Cardano Dijkstra hard fork (Linear Leios, phase 1)

The Dijkstra hard fork is a planned Cardano network upgrade that would introduce the first phase of Linear Leios, a throughput extension to the Ouroboros consensus protocol, and it is targeted for late 2026 (precise date not set). The upgrade concerns ADA and is still tentative.

What is happening

Linear Leios is designed as an extension to Ouroboros rather than a replacement for it. Block producers would publish larger endorser blocks alongside the regular Praos blocks that secure the chain today. A stake-weighted committee then verifies those endorser blocks and issues a certificate for their contents, so certified transactions can enter the ledger through the existing Praos sequence. The underlying proof-of-stake consensus stays intact.

The first phase of the Dijkstra hard fork is targeted for late 2026, subject to governance approval, stake pool readiness and staged parameter decisions. The path to mainnet is not automatic: deployment before the end of the year depends on test outcomes and technical decisions.

Testing is ongoing on the Musashi Dojo public testnet, launched on June 23 and structured across five phases. The first phase, Earth, peaked at 26.8 TxkB/s, a measure of transaction data throughput rather than transactions per second. According to data cited by Input Output, that is roughly six times the ceiling of the current Ouroboros Praos protocol. A separate September test demonstrated about 1,000 transactions per second. The documentation describes a broader target of two to thirty times current capacity, and initial deployments are expected to run at more modest levels. The testnet is currently in the Fire phase.

Why it matters

Praos currently favors security over speed. Leios aims to raise throughput well above that ceiling without weakening decentralization, which makes the upgrade one of the most significant scaling steps on the Cardano roadmap. Charles Hoskinson said on October 17 that Cardano will reach his definition of completion "after Leios", though this is a personal standard rather than a formal release declaration.

For ADA holders and stake pool operators, the key factors are governance votes and pool readiness, since both gate the hard fork. For traders, technical milestones do not automatically translate into price moves, and the rollout is likely to be judged by real network performance under production conditions as much as by market reaction.

Key details

• Date: late 2026 (quarter precision); exact date not confirmed
• Project: Cardano
• Coins: ADA
• Category: Network Upgrade
• Status: tentative, subject to governance approval, pool readiness and staged parameter decisions
• Source: https://finance.biggo.com/news/f091f44f-00c9-4e26-a100-9e65d6da37ac